Organic EL devices are light emitting devices comprising a thin film containing a fluorescent organic compound interleaved between a cathode and an anode. Electrons and holes are injected into the thin film where they are recombined to create excitons. Light is emitted by utilizing luminescence (phosphorescence or fluorescence) upon deactivation of excitons.
The organic EL devices are characterized by plane light emission at a high luminance of about 100 to 100,000 cd/m.sup.2 with a low voltage of about 10 volts and light emission in a spectrum from blue to red color by a simple choice of the type of fluorescent material.
The organic EL devices, however, are undesirably short in emission life, less durable on storage and less reliable because of the following factors.